Eventually, i'd like to put the backplane into a a larger chassis and make it a little more visually appealing. Yes, you are very right about getting bitten by HV if one were to try and fondle the transformer areas but so far it's been pretty safe. I've touched very close to it and not been bit.
I chose medical grade SMPS with some very low ripple specs (~50mV p-P). I didn't bother with any post filtering for this and it does sound very nice and just as good as my PP KT-88 amp, maybe better... but I think I will add a small CRC filtering section in a new chassis. I'll put a metal cage over them when I get a chance. It was strictly a prototype build to try and understand how much active heatsinking is required for the design (without much knowledge of thermal dynamics or outside help) so it went though several iterations in my little machine shop. I try to get things as far as I can go before asking for help. Yes, it is truly myfirstamplifier. LOL. I thank Papa Nelson for his thoughts and suggestions along the way and especially his circuit design that he gave to me free. I hold him in high regard for this even if it is not going to measure close to his original design criteria.
I noticed that since this amp was built, an update with two pots was added to trim the DC bias offset levels of the JFET input stages or do other things aswell? I am interested if the FETS I chose at the time can be improved if I put the pots in instead of using the fixed resistors. There was some changes made to schematic/pcb and no official ECN was made. I found this out by looking at the boards diyaudiostore is selling. It is very possible I overlooked FET matching or tuning any of the stages using trimpots.
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Interested to try the LiPo batteries as well, can you please share your set-up?
ZM, I shall check the amplifiers anyway, and perform some minor mods. I shall measure as well. I have some thermal fuses that should have been installed a long time ago. Also, the top covers are closed, I exchanged the perforated ones due to fear of the cocktail effect….. beverages into the amplifiers. I am so lazy these days, but I promise…..
